help from honda guys

I have a 90 civic. I think it's a D15B2. I want to replace the thermostat.

I see I can buy the thermostat, thermostat gasket, and thermostat housing gasket.

Do I need both gaskets or just one?

http://www.partsgeek.com/catalog/1990/honda/civic/cooling_system/thermostat_gasket.html
http://www.partsgeek.com/catalog/1990/honda/civic/cooling_system/thermostat_housing_gasket.html

I'm looking at getting the NTC thermostat here:
http://www.partsgeek.com/catalog/1990/honda/civic/cooling_system/thermostat.html

Thanks. I'm assuming the housing and cover should be fine and no need to replace that.

I have never come across that thermostat housing gasket..All the ones I have ever done I have only needed the thermostat gasket...

you just need the rubber seal gasket.

i did one a while back and i remember just using the rubber one that comes with the thermostat

I usually do the rubber gasket and put some RTV on it for good measure....

yeah especially if its an napa or oreilys t stat and gasket kit, ive never not had one leak unless i coated it with rtv